Objectives　Bonding failure is lack of parental emotional relationship between a parent and their infant. This study aims to investigate the association between father's involvements with their partner during pregnancy.

Methods　A total of 1,957 partners of pregnant women who had visited three maternity hospitals in Sapporo from May 2016 to December 2017 were included in the study. Self-administered questionnaires were distributed to participants at 2,435 weeks gestation and at 6–8 weeks postpartum. The fathers who responded to both the questionnaires were included in the analysis. The participants' relationship with their partners during pregnancy was rated using two questions— whether they help their partner with personal care and household chores, and whether they consult with their partner. Answers for both questions were given on a scale of 0 to 4. A total score of 6–8 points was defined as a high-score group, 3–5 points as a mid-score group, and 0–2 points as a low-score group. Bonding failure was evaluated using the Japanese version of the Mother-Infant Bonding Scale (MIBS-J). The cut-off value was the score that included the top 10% with the highest degree of bonding disorder. A logistic regression was used to analyse the association between involvement with a partner during pregnancy and bonding failure. The confounding variables were father's age, household income, father's average working hours, previous pregnancy, history of abortion/a stillbirth/the death of the child, and partner's prepartum depression during pregnancy.

Results　391 fathers responded to the initial questionnaire, and 86.4% of them filled out the second questionnaire up to 2 months postpartum, 10.6% up to 3 months, 2.5% up to 4 months, and 1.0% up to 5 months. Of these, 375 were included, excluding those with missing questionnaire items. 255 fathers were in the high score group of the involvement with partner during pregnancy, 48 had bonding failure, 35 had LA, and 17 had AR. The OR based on the high score group of involvement with partner during pregnancy for bonding failure was 4.81 (1.88–12.33) for mid-score group, and 6.89 (1.40–33.93) for low-score group, and for LA, 2.21 (0.97–5.04) for mid-score group, and 6.40 (1.54–26.68) for low-score group; however, AR showed no respectively significant association (trend P 0.0005, 0.0053, 0.6859).

Conclusions　The results suggest that a father's unfavorable involvement with his partner affects the bonding with their infant. This suggests that involvement with a partner during pregnancy is an important factor in preventing bonding failure in fathers.

Objective　This study aimed to qualitatively analyze changes in the health status and factors affecting technical intern trainees over time during their first year in Japan and examined the necessary support for healthy living.

Methods　The study targeted sixteen technical intern trainees who had been living in Japan for almost four months. The study was conducted quarterly in a year, using semi-structured interviews to measure physical and mental health conditions, injury or illness, subjective symptoms, and training and daily life conditions. Dietary content was assessed using photographs taken by participants. Health-check results were collected when available. Data were classified into the six components of the International Classification of Functioning, Disability and Health (ICF), and further qualitative data were analyzed inductively for health-affecting factors using qualitative longitudinal analysis.

Results　The types and timing of illnesses, injuries, subjective symptoms, and health-affecting factors varied. Stress and concerns were experienced by more than 56.3% of each study's participants and more than 44.4% had the possibility of a mood or anxiety disorder. The participants with heavy labor had musculoskeletal disorders in the first half of the study period. The health-check results were in Japanese and some participants did not fully understand them. Fifteen categories were extracted as health-affecting factors:《sleeping conditions》,《joy of independence and anxiety》,《decreased vitality and fatigue》,《undertaking the training》,《communication skills and efforts to learn Japanese》,《efforts for self-health care》,《adaptation to Japanese lifestyle》,《leisure and interaction with Japanese people》,《religious activities》,《training environment》,《living environment》,《support from friends, family and workplace》,《natural environment and economic trends》,《saving-oriented lifestyle》, and《motive for coming to Japan and self-evaluation after one year》.

Conclusion　The technical intern trainees experienced various physical and psychological symptoms. Support in maintaining and promoting positive aspects of health-affecting factors and removing negative aspects is important for the health of trainees. In addition, it is important to support the improvement of the health literacy of trainees by offering information on exercise facilities and medical institutions providing health-check services in multiple languages, and improving means of communications through cooperation with related organizations and the use of regular channels by trainees. Furthermore, involving healthcare professionals in “regional councils” is necessary.

Objectives　Medical insurers have applied a reminder (i.e., recall) system to improve the implementation rate of specific health guidance. However, the effectiveness of the system has not been verified. This study aims to examine the effectiveness of two methods of specific health guidance reminders (i.e., letter and telephone) using a randomized controlled trial.

Methods　Subscribers of National Health Insurance in Yokohama City, Kanagawa Prefecture, who were eligible for specific health guidance in 2020, were recruited. A specific health examination questionnaire was used to identify participants intending to use health guidance. The intervention period was from September to November 2020, with 252 people being randomly assigned to one of the three groups: a “no-reminder group,” “a letter-reminder group,” or “a telephone-reminder group” (84 people each). Those in the letter-reminder group received a reminder by mail and those in the telephone-reminder group received a reminder by phone from a public health nurse two weeks after the specific health guidance coupon was sent to the participants by mail. The outcome showed the utilization rate of specific health guidance. Chi-square tests were performed to compare the three groups and conduct multiple comparisons (post-hoc test).

Results　The participants had a mean age of 61.4±11.0 years and 70.6% were male. There was no difference among the three groups in terms of demographic characteristics and the results of specific health examinations. The utilization rates of specific health guidance were 20.2% in the no-reminder group, 22.6% in the letter-reminder group, and 20.2% in the telephone-reminder group; thus, the three groups did not significantly differ (χ²=0.191, P=0.909). Multiple comparisons also showed no difference between any two groups. However, in the telephonereminder group, 56.0% of the participants themselves or their family members could be reached by a public health nurse, and their utilization rate was higher than those participants whom a public health nurse could not reach.

Conclusion　Neither letter nor telephone reminders changed the participants' utilization rates of specific health guidance compared to those with no reminder. Although the effectiveness of a telephone reminder might be underestimated, this study suggests setting a lower priority in reminding those who intend to use health guidance.

Objective　We examined the effectiveness of governmental declarations on the changing temporal trends in the incidence of COVID-19 cases with unknown transmission routes (unlinked cases) before SARS-CoV-2 vaccines became available in Osaka.

Methods　Seven-day moving averages of the incidence of unlinked COVID-19 cases were calculated using daily reports posted on the official website of the Osaka Prefectural Government for the third (October 10, 2020–February 28, 2021) and fourth COVID-19 waves and about one week before and after (February 23, 2021–June 27, 2021). Then, we calculated daily percentage changes and identified dates of significant change (“Joinpoint”) with a Joinpoint regression analysis. The date of a major change in the behavior of prefectural residents associated with the risk of infection (the date of a sudden change in behavior) was defined as the date counting backward from each Joinpoint date and considering the incubation period and interval between the date of onset and disclosure of the daily report. Subsequently, we examined the temporal relationships between the declaration date and defined date of the sudden change in behavior associated with the risk of infection.

Results　Five Joinpoint dates contributing to a significant downward trend were identified: November 23, 2020, and in 2021, January 7, January 18, April 12, and April 30. We defined dates of sudden changes in behavior from each Joinpoint date from the corresponding time lag (8 to 9.9 days): in 2020, November 13 and December 30; in 2021, January 9, April 4, and April 22. Regarding the five estimated dates, the second emergency declaration was issued on January 9, 2021. Further, the first introduction of priority preventive measures was given on April 4, 2021. April 22 fell between the date that the third emergency declaration was requested and the date of its issuance.

Conclusion　These descriptive epidemiological findings suggest that the issuance of these declarations could be triggers that reinforced infection avoidance behavior among Osaka prefectural residents, which resulted in the downward trends in unlinked COVID-19 cases.